[apple/xnu.git] / libkern / i386 / OSAtomic.s

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

#;***************************************************************************
#;* Boolean OSCompareAndSwap(SInt32 oldValue, SInt32 newValue, SInt32 *ptr) *
#;***************************************************************************

	.globl _OSCompareAndSwap
	.globl _OSCompareAndSwapPtr

_OSCompareAndSwap:
_OSCompareAndSwapPtr:
	movl		 4(%esp), %eax	#; oldValue
	movl		 8(%esp), %edx	#; newValue
	movl		12(%esp), %ecx	#; ptr
	lock
	cmpxchgl	%edx, 0(%ecx)	#; CAS (eax is an implicit operand)
	sete		%al			#; did CAS succeed? (TZ=1)
	movzbl		%al, %eax		#; clear out the high bytes
	ret

#;*****************************************************************************
#;* Boolean OSCompareAndSwap64(SInt64 oldValue, SInt64 newValue, SInt64 *ptr) *
#;*****************************************************************************

	.globl _OSCompareAndSwap64

_OSCompareAndSwap64:
	pushl		%edi
	pushl		%ebx

	movl		 4+8(%esp), %eax	#; low 32-bits of oldValue
	movl		 8+8(%esp), %edx	#; high 32-bits of oldValue
	movl		12+8(%esp), %ebx	#; low 32-bits of newValue
	movl		16+8(%esp), %ecx	#; high 32-bits of newValue
	movl		20+8(%esp), %edi	#; ptr
	lock
	cmpxchg8b	0(%edi)		#; CAS (eax:edx, ebx:ecx implicit)
	sete		%al			#; did CAS succeed? (TZ=1)
	movzbl		%al, %eax		#; clear out the high bytes

	popl		%ebx
	popl		%edi
	ret

#;*******************************************************
#;* SInt64 OSAddAtomic64(SInt64 theAmount, SInt64 *ptr) *
#;*******************************************************

	.globl	_OSAddAtomic64
_OSAddAtomic64:
	pushl		%edi
	pushl		%ebx

	movl		12+8(%esp), %edi	#; ptr
	movl		0(%edi), %eax		#; load low 32-bits of *ptr
	movl		4(%edi), %edx		#; load high 32-bits of *ptr
1:
	movl		%eax, %ebx		
	movl		%edx, %ecx		#; ebx:ecx := *ptr
	addl		4+8(%esp), %ebx
	adcl		8+8(%esp), %ecx		#; ebx:ecx := *ptr + theAmount
	lock
	cmpxchg8b	0(%edi)		#; CAS (eax:edx, ebx:ecx implicit)
	jnz		1b		#; - failure: eax:edx re-loaded, retry
					#; - success: old value in eax:edx
	popl		%ebx
	popl		%edi
	ret

#;*******************************************************
#; SInt32 OSAddAtomic(SInt32 delta, SInt32 *address) 
#;*******************************************************

	.globl	_OSAddAtomic
	.globl	_OSAddAtomicLong
_OSAddAtomic:
_OSAddAtomicLong:
	movl	4(%esp), %eax		#; Load addend
	movl	8(%esp), %ecx		#; Load address of operand
	lock
	xaddl	%eax, 0(%ecx)		#; Atomic exchange and add
	ret
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
8f6c56a5	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
1c79356b A	28
2d21ac55 A	29	#;***************************************************************************
	30	#;* Boolean OSCompareAndSwap(SInt32 oldValue, SInt32 newValue, SInt32 ptr)
	31	#;***************************************************************************
1c79356b A	32
1c79356b A	33	.globl _OSCompareAndSwap
b0d623f7	34	.globl _OSCompareAndSwapPtr
1c79356b A	35
1c79356b A	36	_OSCompareAndSwap:
b0d623f7	37	_OSCompareAndSwapPtr:
91447636 A	38	movl 4(%esp), %eax #; oldValue
	39	movl 8(%esp), %edx #; newValue
	40	movl 12(%esp), %ecx #; ptr
1c79356b	41	lock
91447636	42	cmpxchgl %edx, 0(%ecx) #; CAS (eax is an implicit operand)
2d21ac55	43	sete %al #; did CAS succeed? (TZ=1)
91447636	44	movzbl %al, %eax #; clear out the high bytes
1c79356b	45	ret
2d21ac55 A	46
	47	#;*****************************************************************************
	48	#;* Boolean OSCompareAndSwap64(SInt64 oldValue, SInt64 newValue, SInt64 ptr)
	49	#;*****************************************************************************
	50
	51	.globl _OSCompareAndSwap64
	52
	53	_OSCompareAndSwap64:
	54	pushl %edi
	55	pushl %ebx
	56
	57	movl 4+8(%esp), %eax #; low 32-bits of oldValue
	58	movl 8+8(%esp), %edx #; high 32-bits of oldValue
	59	movl 12+8(%esp), %ebx #; low 32-bits of newValue
	60	movl 16+8(%esp), %ecx #; high 32-bits of newValue
	61	movl 20+8(%esp), %edi #; ptr
	62	lock
	63	cmpxchg8b 0(%edi) #; CAS (eax:edx, ebx:ecx implicit)
	64	sete %al #; did CAS succeed? (TZ=1)
	65	movzbl %al, %eax #; clear out the high bytes
	66
	67	popl %ebx
	68	popl %edi
	69	ret
	70
	71	#;*******************************************************
	72	#;* SInt64 OSAddAtomic64(SInt64 theAmount, SInt64 ptr)
	73	#;*******************************************************
	74
	75	.globl _OSAddAtomic64
	76	_OSAddAtomic64:
	77	pushl %edi
	78	pushl %ebx
	79
	80	movl 12+8(%esp), %edi #; ptr
	81	movl 0(%edi), %eax #; load low 32-bits of *ptr
	82	movl 4(%edi), %edx #; load high 32-bits of *ptr
	83	1:
	84	movl %eax, %ebx
	85	movl %edx, %ecx #; ebx:ecx := *ptr
	86	addl 4+8(%esp), %ebx
	87	adcl 8+8(%esp), %ecx #; ebx:ecx := *ptr + theAmount
	88	lock
	89	cmpxchg8b 0(%edi) #; CAS (eax:edx, ebx:ecx implicit)
	90	jnz 1b #; - failure: eax:edx re-loaded, retry
	91	#; - success: old value in eax:edx
	92	popl %ebx
	93	popl %edi
	94	ret
	95
	96	#;*******************************************************
	97	#; SInt32 OSAddAtomic(SInt32 delta, SInt32 *address)
	98	#;*******************************************************
	99
	100	.globl _OSAddAtomic
b0d623f7	101	.globl _OSAddAtomicLong
2d21ac55	102	_OSAddAtomic:
b0d623f7	103	_OSAddAtomicLong:
2d21ac55 A	104	movl 4(%esp), %eax #; Load addend
	105	movl 8(%esp), %ecx #; Load address of operand
	106	lock
	107	xaddl %eax, 0(%ecx) #; Atomic exchange and add
	108	ret